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Areas of Severe Thunderstorms and Heat

Scattered severe thunderstorms and excessive rainfall are possible today in the Mid Atlantic, posing a risk for damaging winds and isolated flash flooding. Extreme Heat Warnings are in effect today for northeast Texas into southern Oklahoma and Arkansas. Extreme Heat Warnings are also in effect for the Desert Southwest today into Sunday. Read More >

Current conditions at

LOS ALTOS (LOAC1)

Lat: 37.35472°NLon: 122.14167°WElev: 539.0ft.

NA

63°F

17°C

Humidity 82%
Wind Speed SE 1 MPH
Barometer NA
Dewpoint 57°F (14°C)
Visibility NA
Last update 20 Aug 09:10 AM PDT
Extended Forecast for

Portola Valley CA

  • Today

    Today: Partly sunny, with a high near 80. Calm wind becoming north around 6 mph in the afternoon.

    High: 80 °F

    Partly Sunny

  • Tonight

    Tonight: Mostly cloudy, with a low around 55. South southwest wind around 5 mph becoming calm in the evening.

    Low: 55 °F

    Mostly Cloudy

  • Friday

    Friday: Patchy fog before 7am. Otherwise, mostly sunny, with a high near 78. Calm wind becoming northwest 5 to 7 mph in the afternoon.

    High: 78 °F

    Patchy Fog
    then Mostly
    Sunny

  • Friday Night

    Friday Night: Partly cloudy, with a low around 54. West northwest wind 3 to 7 mph.

    Low: 54 °F

    Partly Cloudy

  • Saturday

    Saturday: Mostly sunny, with a high near 79. Calm wind becoming west northwest 5 to 7 mph in the afternoon.

    High: 79 °F

    Mostly Sunny

  • Saturday Night

    Saturday Night: Mostly clear, with a low around 54.

    Low: 54 °F

    Mostly Clear

  • Sunday

    Sunday: Patchy fog before 8am. Otherwise, mostly sunny, with a high near 81.

    High: 81 °F

    Patchy Fog
    then Sunny

  • Sunday Night

    Sunday Night: Partly cloudy, with a low around 55.

    Low: 55 °F

    Partly Cloudy

  • Monday

    Monday: Patchy fog before 8am. Otherwise, mostly sunny, with a high near 79.

    High: 79 °F

    Patchy Fog
    then Mostly
    Sunny

Detailed Forecast

Today
Partly sunny, with a high near 80. Calm wind becoming north around 6 mph in the afternoon.
Tonight
Mostly cloudy, with a low around 55. South southwest wind around 5 mph becoming calm in the evening.
Friday
Patchy fog before 7am. Otherwise, mostly sunny, with a high near 78. Calm wind becoming northwest 5 to 7 mph in the afternoon.
Friday Night
Partly cloudy, with a low around 54. West northwest wind 3 to 7 mph.
Saturday
Mostly sunny, with a high near 79. Calm wind becoming west northwest 5 to 7 mph in the afternoon.
Saturday Night
Mostly clear, with a low around 54.
Sunday
Patchy fog before 8am. Otherwise, mostly sunny, with a high near 81.
Sunday Night
Partly cloudy, with a low around 55.
Monday
Patchy fog before 8am. Otherwise, mostly sunny, with a high near 79.
Monday Night
Patchy fog after 11pm. Otherwise, partly cloudy, with a low around 54.
Tuesday
Patchy fog. Otherwise, mostly sunny, with a high near 80.
Tuesday Night
Partly cloudy, with a low around 54.
Wednesday
Mostly sunny, with a high near 82.
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Forecast Area
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ABOUT THIS FORECAST

 
Point Forecast:
Portola Valley CA
 37.39°N 122.23°W (Elev. 397 ft)
Last Update:
2:16 am PDT Aug 20, 2026
Forecast Valid:
9am PDT Aug 20, 2026-6pm PDT Aug 26, 2026
 
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Additional Resources

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Chance of Precipitation